Air conditioning system utilizing refrigeration



Nov. 9, 1937. SQM. ANDERSON ET AL AIR CONDITIONING SYSTEM UTILIZINGREFRIGERATION Filed Nov. 23, 1935 2 Sheets-Sheet 1 Nov. 9, 1937. s. M.ANDERSON ET AL 2,098,558

AIR'COfiDITIONING SYSTEM UTILIZING REFRIGERATION Filed Nov. 23',

1935 2 Sheets-Sheet 2 7 WM? 2a 1% Patented Nov. 9, 1937 UNITED STATESPATENT OFF-ICE AIR CONDITIONING SYSTEM UTILIZING REFRIGERATION Samuel M.Anderson and Robert T. Palmer, Sharon, Mass, assignors to B. F.Sturtevant Company, Inc., Boston, Mass.

Application November 23, 1935, Serial No. 51,296

4 Claims. (Cl. 62-417) This invention relates to the conditioning of airand relates more particularly to methods and apparatus for cooling theair within railway passenger cars.

One of the major problems in the cooling of air for railway passengercars resides in the difficulty of supplying the necessary cooling effectduring low train speeds and during stops. Motor driven compressorsenergized from axle driven generators are preferred by the railroads.characteristics of the axle driven generators The are

such that their output is insuflicient to energize the refrigerationapparatus at train speeds low about 20 miles per hour.

In some installations, excess storage battery capacity has been providedfor providing the necessary electrical energy during low speeds andduring stops but this has not proved satisfactory due to the greatexcess of battery-capacity required with resulting weight, depreciation,

etc.

In, other installations, refrigeration storage systems have beenprovided such as indirect refrigeration systems where large quantitiesof water were chilled and stored during high train speeds and then drawnupon during low train speeds and during stops to supply the necessarycooling effect. Such systems have not proved desirable because directexpansion systems due to their simplicity are preferred and further itis not desired to carry the large amount of water or other liquidrequired in such storage systems.

According to this invention, a storage system for storing energy duringhigh train speeds is utilized but the energy is stored in the form ofcompressed air. An axle driven compressor compresses air during hightrain speeds, which compressed air is stored under pressure and releasedunder uniform pressure to operate an air m otor which in turn drives arefrigerant compressor.

According to a feature of this invention,

the

air discharged from the air motor which is chilled due to expansion ispassed over the compressor and condenser coils to cool same and to thusprovide an .efficient refrigeration system.

An object of the invention is to operate the refrigeration apparatus ofan air conditioning system with compressed air.

Another object of the invention is to provide a compressed air storagesystem for' operating the air conditioning apparatus of a railwaypassenger car.

Other objects of the invention will be apparent ther The invention willnow be explained with reference to the drawings of which:

Fig. 1 is a side elevation of a railway passenger car equipped with anair conditioning system according to this invention; 5

Fig. 2 is an end view of the mechanism for driving the air compressor ofFig. 1 from one of the car axles; and

Fig. 3 is a diagrammatic view of the complete apparatus of Figs. 1 and 2together with controls. 10

The car axle 5 drives through the V-belt 6,

the shaft I to which is attached one member of the friction clutch 8.The other friction member of the clutch 8 is attached to the shaft 9 towhich is attached the piston rod ID of the piston 15 of the aircompressor ll. 1

The compressor H discharges through the one way valve I2 into thecompressed air storage tank I3. When the pressure within the tank l3reaches a predetermined maximum, the pres- 20 sure switch ll closes acircuit through the battery 44 and solenoid l5, causing the plunger ofthe solenoid to admit air from the tank l3 passing through the pipe Hito pass through the pipe l1 into the cylinder l8 to move the piston ofthe piston rod l9 which in turn moves the free end of the clutch lever20 causing it to disengage the clutch 8 and to so disconnect thecompressor H from the car axle. The pressure reliefvalve 2| may beprovided as a safety measure.

The air from the storage tank l3 passes through the thermostaticallycontrolled valve 22 into the compressed air motor 23 to rotate same. Therefrigerant compressor 24 is driven by the motor 23 to compress anysuitable refrigerant which is then condensed in the coils 25, expandedthrough the valve 26 and evaporated in the coils 21 in the air coolingcompartment 28.

The thermostat 29 exposed to air conditions within the passenger space,closes a circuit when 4 the desired low temperature is reached,including the battery 30 and the solenoid 3| to operate the valve 22 toshut off the air to the motor 23 when no refrigeration is required.

The air compressor II and storage tank I3 45 are exposed to the heat ofthe outdoor air and from the road-bed since more efficient operation isobtained if the compressed air is heated. Where additional heat isdesired for more eificient operation, the coils 32 within the tank l3may be supplied with steam.

The compressed air motor 23, the refrigerant compressor 24 and thecondenser coils are preferably placed within the well insulatedcompartment 33. The air discharged from the motor 23 due to expansion ischilled and is drawn by the fan 34 over the surface of the compressor 23and coils 25 prior to being discharged from the opening 35 in thecompartment 33. When the air discharged from the motor 23 isinsufllcientinvolume, additional air may be drawn in by the fan 34through the opening 36 communicating with the outside air.

The air cooling compartment 28 may be mounted in one end and in the roofzone of the car, as illustrated by Fig. 1, and the air may be dischargedinto the passenger space through, one or more longitudinal ducts or inany other suitable manner. The requisite quantities of recirculated andoutside air are drawn in by the fan 31 driven by the motor 38. The motor38 may be an air motor or due to its slight energy requirements may bean electric motor energized from the usual car lighting circuit.

With the system described. due to the compressibility of air and therelatively high efficiency of a well designed compressed air system,sufficient energy may be stored with minimum equipment and expense tosupply the refrigerating requirements during ordinary low train speedsand during scheduled stops as well as for precooling purposes.

While one embodiment of the invention has been described for the purposeof illustration, it should be understood that the invention is-not to belimited to the exact arrangement described as many departures willsuggest themselves to those skilled in the art after having had accessto this disclosure.

What is claimed is:

1. Air conditioning apparatus for a railway passenger car comprising aircooling means, a refrigerant compressor, a condenser, an air motordriving said compressor, a compressed air storage tank, means forheating the air in said tank, an axle driven air compressor feeding intosaid tank, and means for cooling said condenser with the air dischargedby said motor.

2. Air conditioning apparatus for a railway passenger car comprising aircooling means, a refrigerant compressor, a condenser, an air motordriving said compressor, a compressed air storage tank, means forheating the air in said tank, an axle driven air compressor feeding intosaid tank, means for cooling said condenser and said refrigerantcompressor with the air discharged by said motor, and means forsupplying other air for cooling said condenser and said refrigerantcompressor when the air discharged by said motor is insufficient. v r

3. Air conditioning apparatus for a railway passenger car comprising aircooling means, a refrigerant compressor, an axle driven air compressor,a compressed air storage tank receiving air under .pressure from saidair compressor, means for heating the air in said tank, a compressed airmotor connected' to said refrigerant compressor and energized from saidtank, and means for controlling the supply of air to said motor.

4. Air conditioning apparatus for a railway passenger car comprising aircooling means, a refrigerant compressor, a condenser, an air motordriving said compressor, a compressed air storage tank, an axle drivenair compressor feeding into said tank, an insulated compartmentenclosing said motor, said refrigerant compressor and said condenser,means for discharging the air from said motor into said compartment, andmeans for passing outside air through said compartment.

SAMUEL M. ANDERSON. ROBERT T. PALMER.

